In recent years, there has been proposed a glasses type information terminal configured to represent information based on a sensation of wearing ordinary glasses. For example, in the eye mount video display device disclosed in Patent Literature 1, a liquid crystal display panel is arranged at a portion corresponding to a glasses lens, and the liquid crystal display panel is configured to be connected to a computer device. Further, in the video display device disclosed in Patent Literature 2, light having a brightness that has been changed in accordance with an input video signal is converted into beam light. The beam light is two-dimensionally scanned, and the scanned beam light is guided to an eyeball of the wearer via an integrated mirror arranged at a site corresponding to a glasses lens.
In both the device disclosed in Patent Literature 1 and the device disclosed in Patent Literature 2, a display panel for displaying an image or video (hereinafter referred to as “image”) is formed, or appears to the wearer as if it is formed, on a site corresponding to the glasses lens. Therefore, a processing module for image processing and an optical mechanism for displaying the image are required, which not only place a burden on the body of the wearer, but also appear weird to a person seeing the wearer. Normally, a person cannot directly view the image with one eye and the surrounding area of the person with another eye. Therefore, the wearer of a related-art glasses type information terminal such as that disclosed in Patent Literature 1 or 2 may be unable to concentrate on his or her surrounding area when the image is displayed, and hence his or her everyday activities may be hindered.
As a technology for solving such a problem, in the head-worn information notification device disclosed in Patent Literature 3, a display unit is arranged at a position inside a field of view of a user and outside the field of view visible through the glasses lens when the user wears the glasses, and reception of information is notified to the user via light emitted by the display unit.